Britain’s highest court ruled on Wednesday that only biological and not trans women meet the definition of a woman under equality laws, a landmark decision greeted with concern by trans supporters but welcomed by the government as bringing clarity. The much anticipated ruling centred on whether a trans woman with a gender recognition certificate (GRC), a formal document giving legal recognition of someone’s new gender, is protected from discrimination as a woman under Britain’s Equality Act. The decision confirms that single-sex services for women such as refuges, hospital wards and sports can exclude trans women, clearing up legal ambiguity. Transgender campaigners said the decision could lead to discrimination, especially over employment issues.